Frost Dates for 18660 — Wapwallopen, Pennsylvania

Half of springs at Benton 3 NE, PA see their last 32°F night by May 4; only one in ten is past it by April 21, and one in ten still has one after May 19. Planting tender crops after May 10 leaves a 30% risk of a frost on them, after May 14 20%, and after May 19 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 72% of the 176 Pennsylvania stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 11 in half of years, as early as September 29 one year in ten, and holds off past October 27 one year in ten. A hard freeze of 28°F follows 13 days later, around October 24; in spring the one-in-ten date for 28°F is May 10, 9 days before the 32°F one. The freeze-free season lasts 159 days in a typical year, shorter than at 76% of the 176 Pennsylvania stations; it reaches 179 days one year in ten and falls short of 139 one year in ten. On average 145 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 11 days longer, to about May 15, and return around October 1. Severe cold of 16°F or below comes every winter, usually between December 1 and March 21.

July is the warmest month at Benton 3 NE, PA, averaging 80°F by day and 58°F at night; January is the coldest at 33°F and 16°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 60% of years.

Warmth for growing adds up to 2,377 growing degree days a year (base 50°F), fewer than at 83% of the 176 Pennsylvania stations. 33% of them (781) have built up by the end of June, and July adds the most, 600. Precipitation totals 48.6 inches a year, most in September (4.9") and least in February (2.6"); May to September bring 48% of it.

The nearest other station, Francis E Walter Dam, PA, 18 miles east of Wapwallopen and 414 feet higher, has a last frost 3 days later (May 7), a first frost 5 days earlier (October 6), a season 6 days shorter.

The first measurable snow (0.1 inch or more) in Wapwallopen usually arrives around November 13, and the last of the season around April 1. Those are the middle dates across the winters of 1991–2020 at West Hazleton 3.2 NNE, PA, 6.6 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 33 days after the last snow.

ZIP 18660 is 17 miles from Benton 3 NE, PA, which stands at 1,095 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 7 other ZIP codes share the station; its figures are presented in full for 18603 (Berwick). The 2023 USDA Plant Hardiness Zone Map lists ZIP 18660 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.